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<html lang="en">
<head>
    <meta charset="UTF-8">
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    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        // 基础写法
        const Sum = (a, b) => {
            return a+b 
        }
        console.log(Sum(1,2)) // 3

        // 场景
        let ints = [1,2,3]
        console.log(ints.map(function (i) {
            return i + 1
        })) // [2,3,4]
        
        console.log(ints.map(i => i + 1)) // [2,3,4]
    </script>
</body>
</html>